A mild electrical current applied to the scalp can supress the brain’s responses when processing motion signals, say Imperial College London researchers. Correctly channelled, these electrical signals would prevent motion sickness, their new research suggests.
“Almost everyone can be made motion sick, with approximately one-third experiencing significant symptoms on long bus trips, on ships, or in light aircraft,” wrote the authors. Hoping to complete their new treatment within 10 years, they believe at that time the misery of motion sickness would end forever.
In the meantime, scientists still do not understand the cause of motion sickness but one popular theory suggests it arises from the confusing messages sent to the brain by our eyes and ears when we are moving. So how might science help us reduce the impact of this disturbing “mental noise,” which causes a terrible queasiness in those prone to motion sickness?
The Imperial College researchers proposed applying transcranial direct current stimulation (tDCS) to the left parietal cortex in order to supress the vestibular system. Responsible for our sense of balance, the vestibular system is crucial to our ability to navigate the world. The researchers say it is also the part of us where motion sickness begins and ends.
And so the research team began their electrical stimulation experiment by recruiting 20 volunteers, an equal number of men and women. For about 10 minutes, these volunteers wore electrodes to electrically stimulate their scalp.
“The currents involved are very small,” Dr. Qadeer Arshad, lead researcher and a professor in the department of medicine, explained in a press release, adding, “and there is no reason to expect any adverse effects from short term use.”
Next, these brave folks sat in a motorized, rotating and tilting chair simulating the motions that make people sick on boats. At this point, the researchers recorded the time it took for each volunteer to report symptoms of seasickness, including what they referred to as “stomach awareness,” the onset of nausea, and finally self-recovery. Because past research has shown people are even more susceptible to motion sickness immediately after recovering from a first bout, the researchers then put the volunteers through a second round of electrode stimulation of the scalp followed again by the (evil!) motorized chair.
What did the research team discover? Following treatment, study participants were less likely to feel nauseous and they recovered more quickly from motion sickness.
Since most of the currently marketed treatments are medicinal and include side effects (such as drowsiness), the researchers believe their potential new cure would be preferred by many people, certainly anyone who works on a ship, say, and cannot afford to be sleepy on the job.
With separate research indicating tDCS improves attention and concentration, the military has expressed an interest in this potential motion sickness treatment, said Arshad. His future motion sickness remedy, as he imagines it, would consist of a device with small electrodes that could be temporarily attached to your scalp before travelling. He also envisions the product being available at neighborhood pharmacies.
Source: Arshad Q, Cerchiai N, Goga U, et al. Electro-cortical Therapy for Motion Sickness.Neurology. 2015.